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• Human Computer Interaction (HCI)
definition
• The importance and scope of HCI
• The evolution of HCI
• Usability
• HCI methodology
• Define HCI
• Explain the importance and scope of HCI
• Discuss the evolution of HCI
• Describe usability in HCI
• Explain the HCI methodology
How many interactive products
are there in everyday use?
* Think for a minute about what you use
in a typical day
Introduction
How many are actually easy,
effortless, and enjoyable to
use?
---• Good programmer/designer
need to understand the nature and needs of the computer
• But the nature and needs of
computer are utterly alien to the nature and needs of the human being who will use it
• When the
programmer/designer overlook how bad the the product it is – instead they see how rich the product is in features and
• They ignore how difficult it is
to use, how many hours it takes to learn etc
• Programmer/designer work
hard to make their product
easy to use --> unfortunately their frame of reference is
THEMSELVES, so they only make it easy to use for other software engineers, BUT not for normal human beings
Click & Print Certificates
◦ "Style Buddy“
“Minor” obvious
problems:
◦ Instructions in title bar,
◦ Right-aligned, vertically-oriented instructions,
◦ Cancel button before OK button
◦ Reference to an "OKAY" button
◦ Use of all capital letters
◦ “sickly green color”
◦ etc.
Well, “…it could be better
…”
Isys Information Architects – Interface Hall of Shame
Good and Bad design…
(cont)
Range of styles evident
through list box ◦ Which also provides
selection style more familiar to user
◦ “inconsistency” fixed
“Minor” things fixed, as
well
◦ (except color)
Clearly, more “usable”
◦ And will explore in detail what that mean
“Better …”
Isys Information Architects – Interface Hall of Shame
Interface provides/conveys the only view of the
“underlying” system
◦ Provides:
Model of task, system capabilities … more later
User interface strongly affects perception of software
◦ Usable software sells better
◦ Unusable web sites are abandoned
Perception is sometimes superficial
◦ Users blame themselves for UI failings
◦ People who make buying decisions are not always end-users
Good and bad design
What is wrong with
the remote on the right?
Why is the TiVo
remote so much better designed?
◦ Peanut shaped to fit in hand
◦ Logical layout and color-coded, distinctive
buttons
What to design
Need to take into account:
◦ Who the users are
◦ What activities are being carried out
◦ Where the interaction is taking place
Need to optimize the interactions users
have with a product
Always should have “good”
interfaces
◦ Computing time (power) is getting cheaper
◦ Users’ time isn’t
◦ Ratio discussed last time
Sometimes must have “good”
interfaces
Disasters happen (notes)
◦ Therac-25 radiation therapy machine
◦ Aegis radar system in USS
Interfaces – Should and Must Do
Right
Leveson, N. (1995). Appendix - Medical Devices: The Therac-25
Software designers (let alone coders!) are not the user
◦ As we’ve discussed
◦ Most software engineering is about communicating with other programmers
◦ UI is about communicating with users
The user is always right
◦ Consistent problems are the system’s fault
…except when the user is not right
◦ Users aren’t designers
Human-computer interaction (HCI) is:
◦ “concerned with the design, evaluation and
implementation of interactive computing systems for human use and with the study of major phenomena surrounding them” (ACM SIGCHI, 1992, p.6)
◦ An “interdisciplinary design science”, Shneiderman
Began by “combining data-gathering methods and
intellectual frameworks of experimental psychology with the powerful and widely used tools developed from computer science…”
… “contributions accrued from educational and
industrial psychologists, industrial and graphic designers, technical writers, experts in human
What is HCI ?(CONT.)
Dix: “HCI is study of people, computer
technology and the ways these influence each other. We study HCI to determine how we can make this computer technology
more usable by people” (1998)
Carroll: “HCI is the study and practice of
Human:
Individual user, a group of
users working together, a sequence of users in an organization
Computer:
Desktop computer, large-scale
computer system, Pocket
PC, embedded system (e.g.,
photocopier, microwave oven),
software (e.g., search engine, word
processor)
User interface:
Parts of the computer that the user
contacts with
Interaction:
Usually involve a dialog with
feedback & control throughout
performing a task (e.g., user
invokes “print” command and
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What is HCI? (cont)
The User
The System
• HCI is the kind of discipline bridging between the
human and the technology
• What can the technology do? How can you build it?
What are the possibilities?
• What are people doing and how would this fit in?
What would they do with it?
• Need to consider the issue of
• Efficiency/Effectiveness
• Emotion
• Economy
• Health • Safety
• Example: a navigation system with poor HCI
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Software Engineering Cognitive Psychology Organizational Psychology Sociology Communications Art Theatre Human Factors Computer Engineering Social Psychology Cognitive Science Management Philosophy Affective Computing
Physical capabilities Methodology Hardware Aesthetics Intelligent interfaces Drama User modeling Dialog Collaboration Cost-benefit
Software Engineering Cognitive Psychology Organizational Psychology Sociology Communications Art Theatre Human Factors Computer Engineering Social Psychology Cognitive Science Management Philosophy Affective Computing
Physical capabilities Methodology Hardware Aesthetics Intelligent interfaces Drama User modeling Dialog Collaboration Cost-benefit
• Human cognition
• Perception; Visual/auditory cognition; Motion
cognition; Memory & attention; Learning;
Language understanding; Mental model and metaphors
• Designing for collaboration & communication
• Information visualization; Online
communities; Presentation styles; Group dynamics; Groupware and discussion-ware
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• Understanding how interfaces/technology
affect users
• Ergonomics; safety-critical systems; work
environments; social and behavioural
impact (individual and group); diversity and the digital divide
• User-centered approaches to interaction
design
• Identify needs and establish requirements;
integrate users into design; prototyping and
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• Usability evaluation
• Observing users; testing and modeling
users; expert evaluations
• Interaction styles
• Virtual environments; Menus and forms;
Commands and natural language; hands-free input
• Interaction devices
• Keyboards; Pointing devices; Speech I/O;
Image and video I/O; other sensory devices;
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• Batch processing
• Timesharing
• Networking
• Graphical display
• Microprocessor
• WWW
• Ubiquitous computing
• Grid computing, clouds
• Human robot interaction
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The Evolution of HCI
• 1950’s
• 1960’s
• 1970’s
• 1980’s
• 1990’s
• 1995’s
• Early interaction
• What were the first
interaction devices?
• Wires, punched
tape and cards, switches, teletype
• Lights
• ENIAC (1943) • MARK 1 (1944) • Stretch (1961)
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• The range of current
devices?
• Keyboard
• Light pen, stylus • Mouse, Touchpad,
touch screen
• Microphone
• Headphone
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• Future devices?
Common use soon?
• Data gloves/suits
(wearable computing)
• Natural language • Head-up display
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